TypeError: Property consequent of ConditionalExpression expected node to be of a type ["Expression"] but instead got null
at Object.validate (/home/forum/nodebb/node_modules/babel-types/lib/definitions/index.js:109:13)

I hope you will figure out, how to solve this issue at least for fresh installs.

After i do this, everything is OK, no errors.
Then i choose Oxide theme in admin panel and do "rebuild and restart". No matter, how i do this, via admin panel or with shell command "./nodebb upgrade && ./nodebb restart" the same error appears during build, when Oxide theme is selected.

If it works for you, keep it up.
The semi-official way to do this is to fork the plugin you want to use, and make the appropriate changes.
Then, add the original repo as an upstream branch (using lavender as an example):
git remote add upstream https://github.com/NodeBB/nodebb-theme-lavender.git
When you want to update to the latest lavender for your theme, merge or rebase:
git checkout master && git fetch upstream && git merge upstream/master

@Nisthar said:
@a_5mith said:
@Nisthar said:
some of my users are complaining that theme is not very user friendly.
And they recommended that as a better alternative? That black on blue combination is something else.
My recommendation would be to role with Lavender, then adjust the theme to match the dark theme you're going for. I had a lightbulb in my header that switched between dark and light on my old theme. Will do it for persona at some point. But I'm in no rush.
I think lavender theme does not support custom skins like persona.
Not as well, but the bootstrap custom skins are a bit flaky anyway. IMO obviously. If you want a theme you're happy with. You'll have to roll your own or get the nodebb guys to quote you for the work. There isn't a one size fits all theme unfortunately unless you know how to write CSS.